WASHINGTON — Yelps of support and echoing applause greeted the voice booming over the loudspeakers Wednesday at the scheduled start of practice for the East Regional’s fourth seed: “Coached by Jim Boeheim, please welcome the Syracuse Orange!”

And ... nothing. No sign of Boeheim or any of his players. Not until 6˝ minutes later did they finally make their way onto the court they’ll return to Thursday night to face No. 1 seed Indiana in the NCAA tournament’s round of 16.

Syracuse never really did show up the last time it played a game at this arena: The Orange lost their Big East regular-season finale three weeks ago against host Georgetown 61-39, their fewest points since December 1962 and fourth loss in five games.

Maybe so. But since that disappointing performance, Syracuse (28-9) has gone on a run, winning five of its last six games to reach the Big East tournament final and join Indiana (29-6), No. 2 Miami and No. 3 Marquette to form the only group of 1-4 seeds left in any NCAA region this year.

It’s only the 15th time since the tournament expanded to 64 teams in 1985 — and first since 2009 — that the four highest seeded teams advanced to the regional semifinals, according to STATS LLC.

“That probably is a little surprising,” Indiana freshman guard Yogi Ferrell said. “It shows that we are all high-level programs, and all great teams, and we know how to win.”

No Florida Gulf Coasts in this crowd, that’s for sure. This is a collection of college basketball’s big boys, with two teams from the Big East, and one each from the Big Ten and Atlantic Coast Conference. Three of the four have won the national title at least once, including Syracuse in 2003.

That championship, Boeheim said, allowed him to finally move past his team’s loss to Indiana in the 1987 final — aka “The Keith Smart Game” — the last time these two schools met in men’s basketball.

“When you lose a game like that, you really almost never get over it,” Boeheim said. “I got over it in 2003. I probably thought about it for those (16) years, most of the time. I never think about it anymore.”

Syracuse will confront Indiana on Thursday with its 2-3 zone, typically tough for teams that aren’t used to seeing that sort of system.

As Indiana coach Tom Crean put it: “The challenge never ceases.”

“No one plays a 2-3 zone the whole 40 minutes. We’ve never seen that before,” said Ferrell, whose 146 assists (a 4.2 average) are the second-most in history by an Indiana freshman, trailing only Isiah Thomas’ 159 in 1979-80.

“You may think that a pass is there, and it’s not there the next second. You may throw it and get a turnover,” Ferrell said. “Visually it’s going to be very tough to find those openings, but if we move well, we’ll be OK.”

Indiana — which got a visit Thursday from Crean’s brother-in-law, Super Bowl champion coach John Harbaugh of the up-the-road Baltimore Ravens — was ranked No. 1 in The Associated Press preseason poll and spent more weeks at the top spot than anyone else in 2012-13.

The Hoosiers were led in scoring (16.7) and rebounding (8.0) by sophomore forward Cody Zeller. It’s junior guard Victor Oladipo, however, who is the contender for national player of the year honors.

Oladipo averaged 13.6 points and 6.4 rebounds this season, was the Big Ten’s defensive player of the year and hit a 3-pointer with 14 seconds left to lift Indiana past Temple last weekend.

Oladipo knows this week’s NCAA regional site well, having played at the arena while in high school at D.C.-area power DeMatha.

“I’m going to have a lot of family and friends here, but at the same time, it’s a business trip. We’re here to be successful,” he said.

“Yeah, I won (on this court) in the past,” Oladipo added. “But that has nothing to do with the future and the present.”

Boeheim probably feels the same way — about Thursday’s site and opponent.